Psyc 552 Ergonomics

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Psyc 552 Ergonomics Biomechanics

• Lecture 4

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Ligaments, Tendons, Facia

• Ligament
• Dense connective tissue that connects bone to
  bone.

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ticle.php/article1268.html
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Flexor Retinaculum
1 scaphoid 2 trapezium 3 pisiform 4 hamate
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son5flexretinacpalmapon.htm
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Tendons

• Tendons
• Attach muscles to bones
• Are surrounded by a sheath called a synovium
• Synovial fluid facilitates gliding
• Fascia
• Dense connective tissue that covers organs or
  parts of organs and separates them from each
  other.

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Collagen fibers

• Collagen fibers form both ligaments and tendons.
• In tendons, the fibers run parallel to one
  another
• In ligaments, the fibers are not parallel

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Muscles

• 3 types of muscles in the body
• Striated
• Cardiac
• Smooth
• Muscles consist of
• Muscle cells
• 3 types of connective tissue
• Nerve fibers

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Muscle Connective Tissue
Image from http//www.biology.eku.edu/RITCHISO/30
1notes3.htm
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Muscle Fibers

• Long multinuclear cylindrical cells composed of
  parallel myofibrils
• Myofibrils
• Composed of 2 sub units called myofilaments
• Myosin
• Actin

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net/BiologyPages/M/Muscles.html
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Muscle Contractile Unit

• Sacromere
• The part of a cross-striated muscle fiber between
  the z-lines

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Nervous Tissue
Image from vv.carleton.ca/neil/neural/neuron-a.h
tml
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Nervous Tissue (cont)

• Two branches
• Sensory
• Motor
• Nerves connect to muscles via the neuromuscular
  junction
• Nerve muscle fiber motor unit

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Muscular Contraction
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le_Contract.html
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Muscle Contraction (cont)
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Energy for Muscles

• Adenosine triphosphate ATP
• Anaerobic metabolism
• Aerobic metabolism